It seems relatively new. I only recently became aware of it. I know there is a huge following of the Lii500 here. I own 2 myself but frankly I think the Opus is more versatile. If the IR WORKED on the Li500 I would like it more….but it simply does not. I’m hoping the C4 is the best of both worlds. I got it from Gearbest with coupon for $25. GearBEST's Sale . Rovyvon A5 $15.99 . Convoy S21 $15.99